Gear finishing machine



June 13, E@ w. A. SGHULTE fi v GEAR FINISHING MACHINE Filed Aug. 16, 1944 T Sheets-Sheet l INVENTOR. WILLIAM A. SCHULTE ATTORNEYS June 13, 1950 w. A. scHuL'rE g fi GEAR FINISHING MACHINE Filed Aug. 16, 1944 '7 Sheets-Sheet 2 ZNVENTOR.

WI LL! AM A. SCHULTE.

ATTORNEYS June 13, 0:

w. A. scHULTE GEAR FINISHING MACHINE Filed Aug. 16, 1944 7 Sheets-Sheet s ZNVEN TOR,

BY WILLIAM ASCHU 41M TTO R NEYS .Fune E, 1950 w. A. SCHULTE GEAR FINISHING MACHINE 7 Sheets-Sheet 4 Filed Aug. 16, 1944 INVENTOR.

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lmv E M A Tf'dR NE VS June 13, 1950 w. A. SCHULTE 2,511,418

' v GEAR FINISHING MACHINE Filed Aug. 16, 1944 '7 Sheets-Sheet 5 June 13, 1950 w. A. SCHULTE 2,511,418

GEAR FINISHING MACHINE Filed Aug. 16, 1944 v 7 Sheets-Sheet 6 (9- y I WILLIAM A.SGHULTE.

ATTOR NEYS Patented June 13, 1950 GEAR FINISHING MACHINE vymam A. some. Detroit, Mich., assignor to National Broach & Machine Company, Detroit, Mich., a corporation of Michigan Application August 16, 1944, Serial No. 549,701

The. invention relates to gear finishing machines of that type in which the gear to be flnished is run in mesh with a conjugate cutter and is simultaneously axially reciprocated in relation thereto. More particularly, the invention relates to heavy duty machines of this type designed to operate on gears of large dimensions and proportionate weight.

It is the object of the invention to provide means permanently mounted on the machine facilitating accurate settingof the work so as to obtain a high degree of perfection in the finished product.

It is a further object to provide means for testing the accuracy of the setting during the progress of the work so that correction can be made before the finishing out. With these objects in view the invention consists in the construction as hereinafter set forth:

In the drawings:

Fig. 1 is a plan view of the machine;

Fig. 2 is an end elevation thereof;

Fig. 3 is a rear elevation;

Fig. '4 is an elevation of the work setting indi cator;

Fig. 5 is a plan view thereof;

Fig. 6 is a cross section on lineJ-J, Fig. 4;

Fig. 7 is a cross section on line 1-1, Fig. 4;

Fig. 8 is an elevation of the helix angle and pitch diameter testing means;

Fig. 9 is a plan view thereof;

Fig. 10 is a vertical section;

Fig. 11 is a horizontal section; Y I

Fig. 12 is a cross section on line l2-l2, Fig. .10; and

Fig. 13 is a diagram of the work mounting means.

The specific construction of the gear finishing machine to which my improvements are applied is not the subject matter of the instant invention and I will, therefore, only make general reference to the same. Essentially such machine comprises a bed II on which the work is mounted, a headstock II on said bed for imparting rotary movement to the work, 'a suitable tail- 6 Claims. (01. 9o- 1.s)

toward and away from the axis of the head and tailstocks.

One of the slides III constitutes a tool slide and includes an angularly adjustable head 44 for providing angular adjustment of a cutter I2 carried thereby with respect to the axis of a work piece mounted between the head and tailstock. The cutter I2 is in the form of a gear having teeth l5 adapted to mesh with the teeth of a work gear l'l so as to perform a shaving action thereon when the gear and tool or cutter are rotated in mesh and a relative traverse is provided between the parts in a direction parallel to the axis of the gear.

In the operation of such a machine it is first necessary to adjust the rotary head I4 so that the axis of the cutter tool I2 is at the proper angle. The gear II to be operated upon is then mounted upon the supporting bed I0 so that its axis is parallel to the plane of the carriage l3 and also the direction of movement thereof. The work gear is then coupled to the headstock II which communicates rotary movement thereto and which through the intermeshing relation of the work and cutter will also rotate the latter. Mountings of various designs may be employed for holding the work according to the specific construction of the latter. In some instances the gear to be finished must be mounted on an arbor and the latter journaled in bearings. In other cases the gear and the axle therefor are integral and the latter is journaled in bearings which are in alignment with the headstock. In every case stock (not shown) opposite the headstock for I supporting a work piece in conjunction with the headstock, a reciprocatory carriage I: mounted for movement on the bed It in a direction parallel to the axis of the head and tailstocks, a pair of slides ill mounted on the carriage I: for movement toward and away from the axis of the head and tailstocks. and a separate gaugeslide 24 also mounted on the carriage II for adjustment the mounting must be such that the bearings for the opposite ends of the shaft or arbor can be relatively adjusted vertically and horizontally to secure exact alignment of the axis. As illustrated, I have diagrammatically represented the mounting for the work gear as comprising a pair of column members i1 laterally adjustable on base plates I I secured to the bed It, such adjustment being efiected by screws l9. At the upper ends of these columns are vertically adjustable bearings 20 for receiving the arbor or shaft 2| for the work gear l1. Screws 23 are provided for independently vertically adjusting the bearings 2. in the columns I. This illustration is only diagrammatic but represents any suitable con- 1 struction of mounting which provides for both lateral and vertical adjustment of the arbor bearings.

The subject matter of the instant invention is the construction of the means associated with the machine above described for facilitating and expediting the accurate setting of both the work and the cutter tool. This means includes, first, a means for accurately setting the work in its mounting so that its axis is exactly parallel to the direction of relative reciprocation of the work and the cutter; and, second, means for testing -fr6m time to time during the operation of the machine the accuracy of setting of both the work and the cutter with respect to (a) the helix angle, (b) the pitch diameter.

Work mounting means As previously described, the work is mounted on" the bed ill in bearings 20 which are independ ently adjustable vertically and horizontally. The work gear either on an integral axle or on an arbor is mounted in these bearings after which they must be adjusted to arrange the axis of the work exactly parallel to the direction of movement of the reciprocatory carriage in both horizontal and vertical planes. The means for effecting such accurate adjustment comprises the following construction.

Work setting means a diagonal thereof extending vertically and the lower two sides engaging V-shaped ways of the bearings 25. Caps 28 overlapping the upper sides of the beam retain the same in the bearings. Extending along the upper corner of the beam is a rack bar 21 which is in mesh with a pinion 28 on a transverse shaft 29 journaled in a bracket member 38. In this same bracket member is journaled an operating shaft 3! which extends to opposite sides of the carriage and is provided with hand wheels 32 at each end. A pinion 33 on the shaft 3! meshing with the gear wheel 34 on the shaft 29 forms a step-down transmission through which the rotation of either hand wheel 32 will revolve the pinion 28 to move the rack bar 21 and arm 24. At the free end of the arm 24 is a vertically extending arm 35 which is secured by clamping bolts 36 passing through a longitudinal slot in said arm 35 to threadedly engage the arm 24. The plane of the arm 24 is sufiiciently above the axis of the work to clear an arbor of maximum dimensions and the length of the arm 35 is sufficient to permit of downward adjustment to the work axis. An indicator gauge 3? is mounted on the lower end portion of the arm 35 so that its actuating member 37 may be moved into contact with a registering point in the work arbor. The gauge has a shank 31 which is engageable alternatively with two recesses in the arm 35 so as to mount the gauge in two positions thereon. The arm 35 has also mounted at its lower end a bell crank lever 38 having the arms 38 and 38''. When the gauge is mounted in its upper position on the arm 35, the arm 38 of the bell crank lever will extend horizontally beneath the actuating member 3! while the arm 38 will extend vertically downward. In this position of the parts a bearing 38 on the arm 38 may be moved laterally into contact with the side of the work arbor to effect an indication on the gauge. On the other hand, when the gauge is in its lower position on set the axis of the work in exact parallelism to the direction of movement of the carriage, the procedure is, as follows. First, the arm 24 is projected over the work arbor to bring the member 37 of the gauge substantially into the vertical plane of the axis of the work, this being accomplished when the oarirage I3 is in a position to arrange said gauge near one end of the arbor. The arm 35 is next adjusted downward to bring the member 3! of the gauge into contact with the surface of the'arbor while the gauge registers zero. The bolts 36 are tightened to hold the parts in this position after which the arm 24 is retracted so that it may be moved with the carriage 3 to the opposite side of the work and near the opposite end of the arbor. The arm 24 is .then again projected to bring the member 31 into the same vertical plane which will indicate by the gauge whether or not the axis of the work is parallel to the horizontal plane of the carriage. If out of alignment, then the bearing 20 at the corresponding end of the arbor may be raised or lowered until the gauge registers zero. The same procedure may be followed to determine whether the axis of the work is parallel to the direction of movement of the carriage. In this case, the gauge 37 is in its upper position on the arm 35 and the latter is lowered until th point 38 of the bell crank lever 38 is substantially in the horizontal plane of the work axis. The arm 26 is then moved until the bearing 38 on the bell crank lever 38 contacts with the side of the work arbor with the gauge indicating zero. The test is then made at the opposite end of the arbor and, if alignment is not correct, then the bearing 23 at this end is adjusted laterally until zero is indicated on the gauge.

With the construction as thus far described, it has been stated that the arm 24 is projected and retracted by operation of the hand wheel 32. It is, however, necessary to indicate the amount of this movement so that after retraction of the arm it can be again projected to precisely'the same position. This is accomplished by the following construction. 4b is a member mounted on a slideway 4| which latter is integral with the arm 24. 42 is an indicator gauge mounted on the member 40 with its actuating member 42 extending horizontally. 43 is a yoke mounted on the carriage It to embrace the arm 24 and slideway 48, said yoke having a bearing 43a in alignment with the member 42*. The member) is adjusted in the slideway 4! by means of a rack member 44 secured to said slideway and a pinion 45 engaging said rack. This pinion is on a vertical shaft 46 journaled in the member 40 and connected by beveled gear wheels 41 with a transversely extending shaft 48 also journaled in the member 40 and having hand wheels 49 at opposite ends thereof. Thus, by rotating the shaft 68' the member 40 may be moved towards or away from the yoke member 43. When the arm 24 is projected into operative relation to the work arbor, the member 40 is in a position where the gauge actuator 42 is separated from the yoke 43. As soon, however, as the arm 24 is properly positioned and the gauge 31 indicates zero, the member 40 is moved towards the yoke 43 to contact the members 42 and 43- and to indicate zero on the gauge 42. After this setting the arm 24 may be retracted and, when it is again projected in a position where the gauge 42 registers zero,

this will be the same previously occupied.

Means for testing the pitch diameter and helix angle M at opposite ends thereof and ,is rotated by a hand wheel 55 through an intermediate transposition as that which it bersfll and'llaco distance- Such spacingmaybeeil'ectedbytheuseofaserlesof gauge bars I! which may be laid end to end within a channel member Il mounted on the way II; A series of bars of different lengths may be built up which, together with a micrometer member 18, will produce the exact dimension. If the nose .pieces contact with the gear teeth before the mission mechanism 56 located within the hollow member. At the front of the slide III is a head 81 which is transversely adjustable for a limited distance on ways I! and ball bearings It. A horizontal rack 60 on the inne face of the head engages a pinion I on a vertically extending shaft 62 which at its upper end has an actuating handle 63. 64 is a plate having a swivel mounting on the head 61 and 85 is a sine bar extending horizontally across theface of the Plate 64. pin 68 extends centrally through both the plate It and bar it being journaled at its inner end in a radial and end thrust ball bearing 61. The sine bar 85 has mounted thereon a pair of slides it. These are secured in different positions of adjustment'by headed bolts 69 engaging a longitudinally extending T slot in the bar and provided at their outer ends with clampingnuts ill. Eachof the slides 68 has secured'thereto to project outward therefrom a conical nose piece H which is adapted to engage the opposite faces of adjacent gear teeth in the work gear to be trimmed.

If the teeth of this gear are helical, then by proper setting of the slides 68 oneof the nose pieces II will enter the space between one pair of teeth, while the other nose piece will correspondingly enter the space between an advance pair of teeth. However, to bring the nose piece into full contact with both teeth of each pair and without the necessity of shifting the position of the work gear, the head 51 can be slightly shifted laterally by rotation of the handle 63. An indicator gauge 12 is mounted on the head 51' and a bearing pin I3 projecting rearward from the sine bar 65 registers with the actuating member 12- of said gauge. ,By this means it may be determined whether or not the sine bar is exactly horizontal and, if not, the amount of its angular displacement from the horizontal.

It will be understood from the above description that the transverse slide ill may be moved by operation 01' the hand wheel 55 so as to bring the nose pieces ll into engagement with the teeth .of the work gear. This may be used to determine whether or not the helix angle of the teeth is correct but another important function is to determine whether the pitch diameter is correct. For the latter purpose it is necessary to exactly measure the distance between the points of bearing of said nose pieces on the gear teeth and the axis of the gear. To accomplish this result, an indicator gauge 14 is mounted on the way 5| adjacent to the cross slide Ill and a cooperating finger I5 is secured to the carriage. The relative positioning of these members is such that the space between the actuating member Il of the gauge and the finger l5 exactly corresponds to the radial dimension between the axis of the work gear and the point of bearing of the nose piece H on the gear teeth. Consequently, to set the nose pieces for a gear or predetermined pitch gauge is at the zero point, the pitch diameter will be too large and will require further shaving of the gear to bring it to the proper dimension. Accuracy in such measurement is also dependent upon eliminating all lost motion between elements of the structure, such as between the swivel plate 64 and the head 51. This I accomplish by placing annular hardened plates 64 in recesses in the members 64 and i1 with-hardened balls 6|" therebetween. I also preferably limit the amount of angular movement permitted to .the plate 84 'and sine bar by means of a pin .6 seated in the member 51 and projecting through an arcuate slotof limited length formed in the outer hardened plate 64 carried by the plate I. and concentric with pin 6. The length of the slot in the 'outer of these members will determine the amount of movement permitted to theplate 64.

Method of operation The method of positioning the work on the bed Ill so that its axis is parallel to the plane of the carriage l3 and direction of movement thereof has already been fully explained. In testing for, correctness of helix angle and pitch diameter the procedure is as follows. The linear pitch LP of the gear is the distance from the center line of one tooth to the center line of an adjacent tooth measured parallel to the center line (axis) of the work gear. The nose pieces II should be set a distance apart which is approximately of the face of the gear teeth but is an exact multiple of LP.. Also, these nosepieces'shouldbeequallyspacedfromthe swivel center. Such setting may be eil'ected by the use of gauge blocks placed between a Meeting cylindrical portion 68' of the pin i and cylindricalportions llof the nose pieces II. To set the sine bar exactly horizontal, an anvil 12" is arranged beneath the gauge 12. On this anvil a gauge block 12 is placed and by resting th pin II of the sine bar on this block, the latter will be positioned horizontal. At th same time, the actuator l2 contacts with the pin I3 and the indicator of the gauge stands at zero. The parts thus positioned are ready for testing the helix angle of the gear teeth. This is accomplished by moving the carriage 50 and also laterally adjusting the head 51 by rotation of the handle 83 until each of said nose pieces is in full contact with teeth on opposite sides thereof. If the gaug indicates a displacement of the sine bar from the horizontal. then the helix angle is not correct and the rotary head of the cutter must be slightly adjusted to correct this angle in a succeeding cut.

To test the gear for pitch diameter, the procedur is as previously set forth including, first, measuring a dimension corresponding to the pitch radius by use of the rod 16 and-micrometer II in the channel 11, and then b adjusting the slide 5| towards the work. If the gauge 14 then indicates zero, the'pitch diameter is con-ect. 0n the other hand, if th gauge is not at zero. the d ree of error is indicated.

Thesinebarandlts associtedparismayalsobe diameter,itisonlynecessarytospacethememrsusedfortestin'gspurgearsorgearsinwhichthe a,s11,41a

7 helix angle is too small for testing by the method previously described. For such tests the gauge is first set to indicate the correct angle tor the teeth and the two nose pieces are engaged with'the same interdental space. The nose pieces also gauge the width of an interdental space at the pitch circle of the gear.

What I claim as my invention is:

1. A machine tool comprising a frame, a'tool carriage reciprocableon said frame along rectilinear ways, a work support for a rotary work piece of such size that serious deflection of the work support under the load of the work piece cannot b avoided, means for adjusting said work support under load to bring the axis of the work piece into parallelism with the ways on which said tool carriage is slidable, and gau n means carried directly by said tool carriage for gauging parallelism between said ways and the axis of said work piece to facilitate adjustment of the work support under load into parallelism with the ways on which said tool carriage is slidable.

2. A gear finishing machine comprisin a frame, a tool carriage reciprocabl on said frame along rectilinear ways, a work support for a rotary work gear of such size that serious deflection of the work support under the load of the work gear cannot be avoided, means for adjusting said work support under load to bring the axis of the work gear into parallelism with the ways on which said tool carriage is slidable, and gau in means carried directly by said tool carriag for gauging parallelism between said ways and the axis of said work gear to facilitate adjustment of the work gear under load into parallelism with the ways on which said tool carriage is slidable.

3. A machine tool comprising a frame, a tool carriage reciprocable on said frame along rectilinear ways, a work support for a rotary work ear of such size that serious deflection of the work support under the load ofthe work gear cannot be avoided, means for adjusting said work support under load to bring the axis of the work gear into parallelism with the ways on which said tool carriage is slidable, and gauging means carried directly by said tool carriage for gau ing parallelism between said ways and the axis of said work gear to facilitate adjustment of the work gear under load' into parallelism with the ways on which said tool carriage is slidable, and additional gauging means on said tool carriage for measuring the helix angle of the work piece.

4. A machine tool comprising a frame, a tool carriage reciprocable on said frame along rectilinear ways, a work support for a rotary work gear of such size that serious deflection of the work support under the load of the work gear cannot be avoided, means for adjusting said work support under load to bring the axi of the work gear into parallelism with the ways on which said tool carriage is slidable, and gau ing means carried directly by said tool carriage for gauging parallelism between said ways and the axis of said work gear to facilitate adjustment of the work gear under load into parallelism with the ways on which said tool carriage is slidable, and additionalgauging means on said tool carriage for measuring the helix angle of the work piece, said last named means comprising a slide movable toward and away from the work piece, a

. 8 swiveled sine bar having members contacting tooth spacesofthegearonthepitch line, and means for gauging the position of said slide when said members are seated in the tooth spaces to indicate the pitch diameter of the gear.

5. A gear finishing machine comprising a frame, rectilinear ways on said frame, a carriage reciprocable on said ways, a work support for a rotary work gear of such size that serious defiection of the work support under load cannot be avoided, adjusting meam for said work support for adjusting said work support under load to bring the axis of a work gear carried thereby into parallelism with the ways. a tool slide and a pair of gauge slides on said carriage, all movable along paths at right angks to the said ways, a gear finishing tool on said tool slide operable to correct helix angle errors in the gear and to reduce the pitch diameter thereof, gauging means on one of said slides eifective to determine parallelism between the axis of said work gear and said ways, and gauging means on the other of said slides eflective to determine the helix angle of the work gear when the axis of the work gear is parallel to said ways.

6. A gear finishing machine comprising a frame, rectilinear ways on said frame, a carriage reciprocable on said ways, a work support for a rotary work gear of such size that serious deflection of the work support under load cannot be avoided, adjusting means for said work support for adjusting said work support under load to bring the axis of a work gear carried thereby into parallelism with the ways, a tool slide and a pair of gauge slides on said carriage, all movable along paths at right angles to the said ways, a gear finishing tool on said tool slide operable to correct helix angle errors in the gear and to reduce the pitch diameter thereof, gauging means on one of said gauge slides effective to determine th helix angle and pitch diameter of the work gear when the axis of the work gear is parallel to said ways, and gauging means on the other of said gauge slides effective to determine parallelism between the axis of said work gear and said ways.

WILLIAM A. SCHULTE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

